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CALIFORNIA GEOPHYSICAL WATER SAMPLING PROTOCOLS <br />' Water Sampling Procedures: <br /> The equipment used to withdraw water from the well will be a PVC <br /> or stainless steel bailer or an electric pump. All equipment <br />' including the bailers, bailing cord, water depth measuring <br /> devise, pump, electric lines and hose must be decontaminated <br /> prior to entering any well . They will be decontaminated by <br />' washing with nonphosphate detergent and rinsed with tap water. <br /> The well will be measured, purged, remeasured and a water sample <br /> will be taken immediately after remeasuring. <br />' MEASURING <br /> The depth to groundwater will be measured from the highest point <br /> 1 on the top of the casing to the surface of the water table. This <br /> point is marked with black on the casing. The measuring devise <br /> used will be an electric conductivity devise which trips a red <br />' light and/or a buzzer when the probe touches water. A minimum of <br /> three measurements will be made at each well , the final reading <br /> will be noted after 2 or more readings do not vary by more than <br />' 0 .01 feet. The total depth of the well will also be measured. <br /> This information along with water parameters mentioned later will <br /> be entered onto the sampling sheet. The casing volume will be <br /> calculated according to the formula supplied on sampling sheet. <br /> FLOATING FREE PRODUCT <br />' The presence of floating free product will be checked by <br /> recording the depth of the water and marking that level on the <br /> probe wire. The probe and wire will be withdrawn from the well <br /> and dried. Liquid paste or chalk will be placed on the probe and <br /> up the side of the wire for 2 feet (could be higher depending on <br /> the depth of the plume) . The probe is then carefully lowered <br /> into the well so that the probe just touches the water table, <br />' care will be taken not to lower the probe below the water table. <br /> Once the probe has buzzed at the water table it is withdrawn <br /> quickly from the well and the liquid level above the water level <br /> point on the probe is recorded. This differential between the <br /> liquid level and the probe water sensing point is the floating <br /> product thickness and will be recorded on the sampling sheet. <br /> Water samples will be obtained as follows: <br /> A) First, one casing volume of water will be withdrawn from the <br />' well ; <br /> B) The parameters of pH, conductivity and temperature will be <br /> measured. The color, odor and presence of a sheen of the purged <br /> water will be noted; <br /> C) A 2nd and 3rd casing volume of water will be withdrawn and the <br /> Parameters remeasured, if the results from the third measuring <br />